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The Fundão tailings dam held back approximately 50 million cubic meters of tailings from an Fe ore mine in the state of Minas Gerais, Brazil. The dam failed on 5 November 2015, releasing tailings into the Rio Doce watershed and causing an environmental disaster in a biodiversity hotspot. To guide conservation action following the event, Brazilian authorities demanded an impact assessment focused on terrestrial species threatened by extinction. Postdisaster impact assessment is substantially more challenging than predevelopment impact assessment. Predisaster baseline data were sparse, and much was unknown about how the Fundão dam failure impacted terrestrial species threatened with extinction. Baseline reconstruction and impact pathway validation and characterization was critical. Ecosystem reconstruction revealed that 1580 ha of terrestrial ecosystems were destroyed, including approximately 480 ha of Atlantic rainforest. Collaboration with local experts identified 346 species of vertebrates, invertebrates, and vascular plants threatened with extinction that were impacted or potentially impacted. Species composition and impacts varied within 4 distinct segments of the Rio Doce watershed. Nine potential impact pathways were identified using data and literature review combined with information provided by regulators, experts, and media. Not all were valid. Validating and characterizing each pathway within each watershed segment involved data evaluation, an ecological risk screening, and field assessments. Impact pathway evaluation proved critical to dispelling misconception, accurately understanding postdisaster impacts, and directing conservation action; the importance of this step cannot be overemphasized. Integr Environ Assess Manag 2020;16:676-680. © 2020 SETAC.A barragem de Fundão armazenava milhões de metros cúbicos de rejeitos de uma mina de ferro no estado de Minas Gerais, Brasil. A barragem se rompeu em 5 de novembro de 2015, liberando rejeitos para a bacia do rio Doce, provocando um desastre ambiental em um hotspot de biodiversidade. Visando orientar ações de conservação após o evento, autoridades ambientais brasileiras demandaram uma avaliação de impactos com foco em espécies ameaçadas de extinção. Avaliações de impacto pós-desastre são substancialmente mais desafiadoras do que avaliações padrão, que antecedem a execução de empreendimentos. No caso de Fundão, dados da linha de base anterior ao desastre eram escassos, e pouco se sabia a respeito de como os vetores de impacto relacionados ao rompimento poderiam ter afetado a biodiversidade terrestre, incluindo a sua magnitude, duração e abrangência espacial. Consequentemente, a reconstrução da linha de base e a validação e caracterização dos potenciais vetores de impacto foram os primeiros passos essenciais. A reconstrução da linha de base para ecossistemas, feita a partir de imagens de satélite, revelou que aproximadamente 1580 ha de ecossistemas terrestres foram suprimidos, incluindo ~480 ha de mata atlântica. Por meio de colaboração com especialistas na biodiversidade local e utilizando fontes diversas de dados e literatura, foram identificadas 346 espécies de vertebrados, invertebrados e plantas vasculares ameaçadas de extinção ocorrentes ou potencialmente ocorrentes nas áreas afetadas. A composição em espécies variou entre quatro distintos segmentos da bacia do rio Doce, assim como os impactos incidentes. Nove potenciais vetores de impacto foram identificados utilizando-se dados e revisões da literatura, além de informações fornecidas por órgãos ambientais e especialistas, e pela mídia. A validação e caracterização de cada vetor de impacto em cada segmento da bacia envolveu a avaliação de dados, uma análise preliminar de risco ecológico, e avaliações em campo. A avaliação de vetores de impacto mostrou-se fundamental para dirimir equívocos de interpretação e acuradamente entender os impactos pós-desastre; a importância desta etapa não pode ser menosprezada. O cruzamento de características biológicas e ecológicas das espécies terrestres ameaçadas de extinção, em cada segmento da bacia, com a caracterização dos vetores de impacto, permitiu a atribuição de consequências dos impactos, constituindo uma maneira efetiva de priorizar medidas mitigadoras com vistas ao alcance de metas de conservação pós-desastre. Integr Environ Assess Manag 2020;16:676-680.

Large carnivore populations are imperiled worldwide through habitat loss, insufficient prey, and intolerance by people, promoting concerns that their populations will persist only in protected areas and remote regions. This assumption is challenged by recent colonization of areas with high human use in the former ranges of several carnivore species, including cougars (Puma concolor). We hypothesized that cougars adjust their behavior to accommodate anthropogenic development, facilitating successful use of modified habitats. We tested this hypothesis using resource selection functions for 42 individual cougars maintaining home ranges across a gradient of anthropogenic development. We evaluated variation in selection among individual cougars by time of day, home-range location (i.e., rural vs. wilderness cougars), and using functional response curves. Cougars stayed further away from both roads and buildings during the day than they did at night, and wilderness cougars showed stronger avoidance of anthropogenic features than did their rural counterparts. Selection patterns of individual cougars varied greatly, and some of this variation was explained by the functional response. For example, cougars decreased their avoidance of some anthropogenic features as those features became more prevalent on the landscape. Failure to account for potential functional responses in habitat selection could lead to overestimation of negative impacts of development for adaptable large carnivores. Given high adaptability to anthropogenic habitat modification displayed by cougars, cougar persistence in increasingly developed landscapes may depend more on human tolerance than on maintaining large tracts of pristine wilderness.

In Alberta, Canada, number of cougar (Puma concolor) mortalities caused by humans has increased rapidly over the past 2 decades. Management agencies sometimes use human-caused mortalities as an index of cougar population trend, which would indicate an increasing cougar population in Alberta, but mortalities may be decoupled from cougar numbers. Some authors suggest that higher human-caused cougar mortalities (primarily due to sport hunting) are causing cougar populations in North America to decline. We used the distribution of human-caused cougar mortalities in Alberta to evaluate change in cougar populations during 1991–2010, a period over which human-caused cougar mortality increased rapidly. We provide evidence that cougars have expanded their range in northern and eastern Alberta in tandem with increasing sport hunting and other sources of human-caused mortality. © 2013 The Wildlife Society.

Population increases of primary prey can negatively impact alternate prey populations via demographic and behavioural responses of a shared predator through apparent competition. Seasonal variation in prey selection patterns by predators also can aff ect secondary and incidental prey by reducing spatial separation. Global warming and landscape changes in Alberta ’ s bitumen sands have resulted in prey enrichment, which is changing the large mammal predator – prey system and causing declines in woodland caribou Rangifer tarandus caribou populations. We assessed seasonal patterns of prey use and spatial selection by wolves Canis lupus in two woodland caribou ranges in northeastern Alberta, Canada, that have undergone prey enrichment following recent white-tailed deer Odocoileus virginianus invasion. We determined whether risk of predation for caribou (incidental prey) and the proportion of wolf-caused-caribou mortalities varied with season. We found that wolves showed seasonal variation in primary prey use, with deer and beaver Castor canadensis being the most common prey items in wolf diet in winter and summer, respectively. Th ese seasonal dietary patterns were refl ected in seasonal wolf spatial resource selection and resulted in contrasting spatial relationships between wolves and caribou. During winter, wolf selection for areas used by deer maintained strong spatial separation between wolves and caribou, whereas wolf selection for areas used by beaver in summer increased the overlap with caribou. Changing patterns in wolf resource selection were refl ected by caribou mortality patterns, with 76.2% of 42 adult female caribou mortalities occurring in summer. Understanding seasonal patterns of predation following prey enrichment in a multiprey system is essential when assessing the eff ect of predation on an incidental prey species. Our results support the conclusion that wolves are proximately responsible for woodland caribou population declines throughout much of their range.

The federal recovery strategy for boreal woodland caribou (Rangifer tarandus caribou) sets a goal of self-sustaining populations for all caribou ranges across Canada. All caribou herds in Alberta are currently designated as not self-sustaining and the recovery strategy requires an action plan to achieve self-sustaining status. At the same time, continued natural resource extraction in caribou ranges may be worth hundreds of billions of dollars. Some regulatory bodies have recognized an opportunity for biodiversity offsets to help meet the caribou recovery strategy’s goals while still permitting economic benefits of development. In this review, we evaluate offset opportunities for caribou in Alberta and practical impediments for implementation. We conclude that a number of actions to offset impacts of development and achieve no net loss or net positive impact for caribou are theoretically feasible (i.e., if implemented they should work), including habitat restoration and manipulations of the large mammal predator-prey system. However, implementation challenges are substantial and include a lack of mechanisms for setting aside some resources for long periods of time, public opposition to predator control, and uncertainty associated with loss-gain calculations. A framework and related policy for offsets are currently lacking in Alberta and their development is urgently needed to guide successful design and implementation of offsets for caribou.

Assessing the impact of large carnivores on ungulate prey has been challenging in part because even basic components of predation are difficult to measure. For cougars (Puma concolor), limited field data are available concerning fundamental aspects of predation, such as kill rate, or the influence of season, cougar demography, or prey vulnerability on predation, leading to uncertainty over how best to predict or interpret cougar–ungulate dynamics. Global Positioning System (GPS) telemetry used to locate predation events in the field is an efficient way to monitor large numbers of cougars over long periods in all seasons. We applied GPS telemetry techniques combined with occasional snow-tracking to locate 1,509 predation events for 53 marked and an unknown number of unmarked cougars and amassed 9,543 days of continuous predation monitoring for a subset of 42 GPS-collared cougars in west-central Alberta, Canada. Cougars killed ungulates at rates near the upper end of the previously recorded range, ...

Autocorrelation has been viewed as a problem in telemetry studies because sequential observations are not independent in time or space, therefore violating assumptions for statistical inference. Yet nearly all ecological and behavioural data are autocorrelated in both space and time. We argue that there is much to learn about the structure of ecological and behavioural data from patterns of autocorrelation. Such patterns include periodicity in movement and patchiness in spatial data, which can be characterized by an autocorrelogram, semivariogram or spectrum. We illustrate the utility of temporal autocorrelation functions (ACFs) for analysing step-length data from GPS telemetry of wolves ( Canis lupus ), cougars ( Puma concolor ), grizzly bears ( Ursus arctos ) and elk ( Cervus elaphus ) in western Alberta. ACFs often differ by season, reflecting differences in foraging behaviour. In wilderness landscapes, step-length ACFs for predators decay slowly to apparently random patterns, but sometimes display strong daily rhythms in areas of human disturbance. In contrast, step lengths of elk are consistently periodic, reflecting crepuscular activity.

In western Canada it is illegal to trap or snare cougars (Puma concolor), but cougars are sometimes caught accidentally in snares placed near carrion baits, a technique commonly used by trappers to harvest wolves (Canis lupus). We studied cougar foraging ecology and survival in west-central Alberta to estimate the propensity for cougars to scavenge, their susceptibility to snaring at trapper bait stations, and the implications these have for managing cougar populations. During 2005-2008, we used data from visits to 3,407 Global Positioning System (GPS) location clusters and .400 km of snow tracking of 44 cougars to locate foraging events and calculate scavenging rates. We identified 83 instances of scavenging, and 64% of monitored cougars scavenged at least once. Scavenging rates were higher in winter (0.12 events/week) than in summer (0.04 events/week), reflecting seasonal variation in carrion availability. Individual cougars scavenged at different rates, and winter feeding on carrion occupied up to 50% of total carcass handling time for some cougars. Based on these results we conclude that cougars are facultative scavengers. A propensity to scavenge made cougars susceptible to snaring causing high annual mortality in radiocollared cougars (0.11, 95% CI 5 0.03-0.21). Provincial cougar mortality data demonstrate that snaring has increased dramatically as a mortality source in Alberta over the last 2 decades. Mortalities of radiocollared cougars during our study were 100% human caused and the addition of snaring mortality to already high hunting mortality resulted in low annual survival (0.67, 95% CI 5 0.53-0.81). Our study is one of the first to identify population-level consequences for nontarget animals killed unintentionally by indiscriminate harvest techniques in a terrestrial ecosystem. Maintaining sustainable cougar harvest where snaring at carrion baits is permitted may require flexible hunting quotas capable of accommodating high cougar snaring mortalities in some years.

Using clusters of locations obtained from Global Positioning System (GPS) telemetry collars to identify predation events may allow more efficient estimation of behavioral predation parameters for the study and management of large carnivore predator–prey systems. Applications of field- and model-based GPS telemetry cluster techniques, however, have met with mixed success. To further evaluate and refine these techniques for cougars (Puma concolor), we used data from visits to 1,735 GPS telemetry clusters, 637 of which were locations where cougars killed prey >8 kg in a multi-prey system in west-central Alberta. We tested 1) whether clusters were reliably created at kill locations, 2) the ability of logistic regression models to identify kill occurrence (prey >8 kg) and multinomial regression models to identify the prey species at a kill cluster, and 3) the duration of monitoring required to accurately estimate kill rate and prey composition. We found that GPS collars programmed to attempt location ...

Researchers consider group size in primates to be determined by complex relationships among numerous ecological forces. Antipredator benefits and better resource defense are the primary pressures for large groups. Conversely, intragroup limited food availability, can result in greater intragroup feeding competition and individual energy expenditure in larger groups, creating energetic advantages for individuals in small groups and placing an upper limit group size. However, the extent to which food availability constrains group size remains unclear for many species, including black howlers (Alouatta pigra), which ubiquitously live in small social groups (≤10 individuals). We studied the relationship between group size and 2 key indices of feeding competition—day journey length and activity budgets—in 3 groups of wild Alouatta pigra at a hurricane-damaged site in Belize, Central America. We controlled for differences in food availability between home ranges (food tree density) and compared both indicators of feeding competition directly with temporal variation in food availability for each group. Our results show no consistent association between resource availability, group size, and either index of competition, indicating that feeding competition does not limit group size at the site—i.e., that larger groups can form without increased costs of feeding competition. The results support the search for other explanations, possibly social ones, for small group size in the primates, and we conclude with suggestions and evidence for such alternative explanations.

This study reports on the diet and activity budgets of Central American black howling monkeys ( Alouatta pigra) at Monkey River, Belize. This is a previously unstudied population, close to the southern boundary of the species range, and it provides comparative data on A. pigra from a new study site. Both diet and activity are within the ranges reported for other A.pigra sites and for mantled howlers ( A. palliata). No age-sex differences could be discerned in either diet or activity, though monthly variation was apparent. The monkeys switch from consuming leaves 86% of the time in January to March to consuming 67% fruit in April to July. This difference was statistically significant, and provided the opportunity to compare activity levels of the monkeys over two dietary periods, one characterized primarily by folivory, the other by frugivory. Howlers are often seen as a relatively inactive species, something that is associated with a low quality, folivorous diet. However, A. pigra have been described as being as frugivorous as possible and as folivorous as necessary. Yet, despite the opportunistic consumption of large quantities of high-energy foods, A. pigra has been observed as conforming to the howler lifestyle, resting as much as 80% of the day. The data in this paper support both of these reports. Black howlers at Monkey River Belize are typically inactive, maintaining high levels of inactivity even during months characterized by frugivory, suggesting that diet is more flexible and varied than is behavior and calling into question the assumption that howler inactivity is due to the digestion of large quantities of leaves.

Although infanticide has been witnessed in other species of howler monkey, and has been inferred for Alouatta pigra, an observed case of infanticide has not previously been recorded for this species. Here we describe the killing of a 2-week-old infant by the resident male of a small social group in southern Belize. The infanticide was witnessed as part of an intensive observational study that began in January 2003. The male was known to have resided in the group for at least 4 months, but it is not known whether he was the father of the infant. The literature proposes three main explanations for infanticide: two adaptive hypotheses (sexual selection and resource competition), and one nonadaptive hypothesis (social pathology). Individual cases of infanticide such as this one are important for comparative purposes, but when examined on their own they are difficult to interpret in relation to established theoretical frameworks. The data presented here show some consistency with the sexual-selection and resource-competition hypotheses, but the lack of critical information (i.e., as to paternity) makes it impossible to draw firm conclusions.